Pliant members for receiving and aiding in the deployment of vascular prostheses

ABSTRACT

A vascular prosthesis deployment device and related methods are disclosed. In some embodiments the deployment device may include a delivery catheter assembly. The delivery catheter assembly may include a pliant member, wherein the pliant member is configured receive a vascular prosthesis. The pliant member may also be configured to aid in incrementally deploying a vascular prosthesis.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/068,521 filed on Oct. 12, 2020 and titled “Pliant Members forReceiving and Aiding in the Deployment of Vascular Prostheses” which isa continuation of U.S. patent application Ser. No. 15/718,419, filed onSep. 28, 2017, now U.S. Pat. No. 10,799,378 and titled, “Pliant Membersfor Receiving and Aiding in the Deployment of Vascular Prostheses,”which claims priority to U.S. Provisional Application No. 62/401,628filed on Sep. 29, 2016 and titled, “Pliant Members for Receiving andAiding in the Deployment of Vascular Prostheses,” all of which arehereby incorporated by reference in their entireties.

TECHNICAL FIELD

The present disclosure relates generally to medical devices. Morespecifically, the present disclosure relates to vascular prosthesisdeployment devices, including deployment devices for self-expandingvascular prostheses such as stents and stent-grafts.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments disclosed herein will become more fully apparent fromthe following description and appended claims, taken in conjunction withthe accompanying drawings. The drawings depict only typical embodiments,which embodiments will be described with additional specificity anddetail in connection with the drawings in which:

FIG. 1 is a perspective view of a deployment device.

FIG. 2 is a cross-sectional view of a portion of the deployment deviceof FIG. 1.

FIG. 3A is a perspective view of a ratchet slide component of thedeployment device of FIGS. 1 and 2.

FIG. 3B is a cross-sectional view of the ratchet slide of FIG. 3A.

FIG. 4 is a side view of a carrier component of the deployment device ofFIGS. 1 and 2.

FIG. 5 is a cross-sectional view of another portion of the deploymentdevice shown in FIGS. 1 and 2.

FIG. 6 is a cross-sectional view of yet another portion of thedeployment device shown in FIGS. 1 and 2.

FIG. 7 is a front view of the deployment device of FIG. 1, illustratingcertain cross-sectional planes described herein.

FIG. 8 is a perspective view of the safety member of the deploymentdevice of FIG. 1.

FIG. 9 is a side view of a portion of the delivery catheter assembly ofthe deployment device of FIG. 1.

FIG. 10 is a side view of another portion of the delivery catheterassembly of the deployment device of FIG. 1.

FIG. 11A is a perspective view of another embodiment of a deploymentdevice.

FIG. 11B is a cross-sectional view of a portion of a delivery catheterassembly of the deployment device of FIG. 11A along plane 11B-11B.

FIG. 11C is a cross-sectional view of a portion of the delivery catheterassembly of the deployment device of FIG. 11A along plane 11C-11C.

FIG. 11D is a side view of another portion of the delivery catheterassembly of the deployment device of FIG. 11A.

FIG. 12A is a side view of yet another portion of the delivery catheterassembly of the deployment device of FIG. 11A with a prosthesis in afirst state.

FIG. 12B is a side view of the portion of the delivery catheter assemblyof FIG. 12A in a second state.

FIG. 12C is a side view of the portion of the delivery catheter assemblyof FIG. 12A in a third state.

FIG. 13A is a cross-sectional view of a portion of another embodiment ofa delivery catheter assembly.

FIG. 13B is a side view of the portion of the delivery catheter assemblyof FIG. 13A, wherein an outer sheath has been removed.

FIG. 14 is a perspective view of another embodiment of a deploymentdevice.

FIG. 15 is a cross-sectional view of a portion of the deployment deviceof FIG. 14.

FIG. 16A is a perspective view of a ratchet slide component of thedeployment device of FIGS. 14 and 15.

FIG. 16B is a cross-sectional view of the ratchet slide of FIG. 16A.

FIG. 17 is a side view of a carrier component of the deployment deviceof FIGS. 14 and 15.

FIG. 18 is a cross-sectional view of another portion of the deploymentdevice shown in FIGS. 14 and 15.

FIG. 18A is a partial cut-away view of a portion of the deploymentdevice shown in FIG. 18.

FIG. 19 is a cross-sectional view of yet another portion of thedeployment device shown in FIGS. 14 and 15.

DETAILED DESCRIPTION

Deployment devices may be configured to deliver a medical appliance to alocation within a patient's body and deploy the medical appliance withinthe patient's body. Though specific examples recited herein may refer todeployment of devices within the vasculature, analogous concepts anddevices may be used in various other locations within the body,including for placement and deployment of medical appliances in thegastrointestinal tract (including, for example, within the esophagus,intestines, stomach, small bowel, colon, and biliary duct); therespiratory system (including, for example, within the trachea,bronchial tubes, lungs, nasal passages, and sinuses); or any otherlocation within the body, both within bodily lumens (for example, theureter, the urethra, and/or any of the lumens discussed above) andwithin other bodily structures.

Furthermore, though specific examples herein may refer to deployment ofvascular prostheses such as stents, deployment of a wide variety ofmedical appliances are within the scope of this disclosure, includingstents, stent-grafts, shunts, grafts, and so forth. Additionally, thedeployment device disclosed herein may be configured to deliver anddeploy self-expanding medical appliances, including stents configured toexpand within a bodily lumen upon deployment.

As used herein, delivery of a medical appliance generally refers toplacement of a medical appliance in the body, including displacement ofthe appliance along a bodily lumen to a treatment site. For example,delivery includes displacement of a crimped stent along a vascular lumenfrom an insertion site to a treatment location. Deployment of a medicalappliance refers to placement of the medical appliance within the bodysuch that the medical appliance interacts with the body at the point oftreatment. For example, deployment includes releasing a crimped orotherwise constrained self-expanding stent from a deployment device suchthat the stent expands and contacts a lumen of the vasculature.

Deployment devices within the scope of this disclosure may be configuredto incrementally deploy a medical appliance. Incremental deployment mayfacilitate desired placement of the medical appliance due to the degreeof control afforded a practitioner during deployment. A practitionermay, for example, desire to deploy a portion of a stent, makeadjustments to placement within the vasculature or confirm the locationof the stent, prior to deploying the remaining portion of the stent.Such processes may be iterative, with a practitioner deploying a portionof a stent, confirming placement, deploying an additional portion, againconfirming placement, and so forth until the stent is fully deployed.

Deployment devices within the scope of this disclosure may be configuredto provide visual, audible, tactile, or other feedback relating to thedegree to which a medical appliance has been deployed. Multiple types offeedback may enhance a practitioner's level of control over theprocedure due to the multiple indications regarding location or degreeof deployment of the medical appliance.

Moreover, deployment devices within the scope of this disclosure mayprovide a degree of mechanical advantage during deployment, for example,through the use of levers to decrease the force used to deploy a device.Mechanical advantage may thus increase a user's comfort and level ofcontrol during use. Still further, deployment devices within the scopeof this disclosure may be ergonomically designed, presenting anactuation input disposed such that a practitioner can directly engageand utilize the device, without repositioning his or her hand or body.Deployment devices within the scope of this disclosure may also beconfigured for one-handed actuation and may be configured forambidextrous use.

It will be readily understood that the components of the embodiments asgenerally described and illustrated in the figures herein could bearranged and designed in a wide variety of configurations. Thus, thefollowing more detailed description of various embodiments, asrepresented in the figures, is not intended to limit the scope of thedisclosure, but is merely representative of various embodiments. Whilethe various aspects of the embodiments are presented in drawings, thedrawings are not necessarily drawn to scale unless specificallyindicated.

The phrases “connected to” and “coupled to” refer to any form ofinteraction between two or more entities, including mechanical,electrical, magnetic, electromagnetic, fluidic, and thermal interaction.Two components may be coupled to each other even though they are not indirect contact with each other. For example, two components may becoupled to each other through an intermediate component.

The directional terms “proximal” and “distal” are used herein to referto opposite locations on a medical device. The proximal end of thedevice is defined as the end of the device closest to the practitionerwhen the device is in use by the practitioner. The distal end is the endopposite the proximal end, along the longitudinal direction of thedevice, or the end furthest from the practitioner.

Again, though the embodiments specifically described below may referencea stent deployment device specifically, the concepts, devices, andassemblies discussed below may be analogously applied to deployment of awide variety of medical appliances in a wide variety of locations withinthe body.

FIG. 1 is a perspective view of a deployment device 100. The deploymentdevice 100 comprises a handle assembly 102 adjacent the proximal end ofthe deployment device 100. An elongate delivery catheter assembly 104extends distally from the handle assembly 102 to a distal tip ordelivery tip 174. The handle assembly 102 may provide a proximal userinput, with one or more components configured to allow a practitioner todeploy or otherwise manipulate a stent disposed within the deliverycatheter assembly 104.

In use, the handle assembly 102 may be disposed outside of a patient'sbody, while the delivery catheter assembly 104 is advanced to atreatment location within the patient's body. For example, the deliverycatheter assembly 104 may be advanced from an insertion site (such as,for example, a femoral or jugular insertion site) to a treatmentlocation within the vasculature. As further detailed below, the deliverycatheter assembly 104 may be configured to be advanced through bends,turns, or other structures within the anatomy of the vasculature. Again,as detailed below, a stent may be disposed within a portion of thedelivery catheter assembly 104 such that a practitioner may deploy thestent from a distal end of the delivery catheter assembly 104 throughmanipulation of one or more components of the handle assembly 102.

FIG. 2 is a cross-sectional view of a portion of the deployment device100 of FIG. 1. Specifically, FIG. 2 is a side view of a portion of thedeployment device 100 of FIG. 1, taken through a cross-sectional planeextending vertically and intersecting a longitudinal axis of thedeployment device 100, when the deployment device 100 is positioned asshown in FIG. 1. The longitudinal axis of the deployment device 100extends along the center of the delivery catheter assembly 104,including along the center of components of the delivery catheterassembly 104 which overlap with the handle assembly 102, such as theintermediate sheath 160, as shown in FIG. 2.

As the handle assembly 102 is configured to be grasped or otherwisemanipulated by a user and the delivery catheter assembly 104 isconfigured to extend to a treatment location within a patient's body,along the longitudinal axis, the delivery catheter assembly 104 extendsin a distal direction away from the handle assembly 102. The proximaldirection is opposite, correlating to a direction defined along thelongitudinal axis, extending from the distal tip 174 toward the handleassembly 102.

FIG. 2 depicts various internal components of the handle assembly 102,exposed by the cross-sectional view. A portion of the delivery catheterassembly 104 is also shown extending from the handle assembly 102. Thehandle assembly 102 comprises a housing 110. The housing 110 surroundscertain components of the handle assembly 102, as shown, providing agrip surface for a practitioner.

The housing 110 is operably coupled to an actuator 120. Manipulation ofthe actuator 120 with respect to the housing 110 may be configured todeploy the stent, as further detailed below. In the depicted embodiment,the actuator 120 is rotatably coupled to the housing 110 by a pin 112.The pin 112 extends from the housing 110 and may be integrally formedwith one or more other portions of the housing 110. As shown, the pin112 extends through a pin aperture 122 in the actuator 120.

Other arrangements for operably coupling the actuator 120 and thehousing 110 are within the scope of this disclosure. For example, thepin 112 may be integral with a portion of the actuator 120 and may bereceived in an opening, sleeve, or aperture formed in the housing 110.Other types of designs of rotatable couplings, including a separatecoupling component such as a hinge are within the scope of thisdisclosure. Still further, a compliant mechanism, such as a deformableflange, may be utilized to rotatably couple the actuator 120 and thehousing 110, including compliant couplings integrally formed with theactuator 120, the housing 110, or both. Moreover, it is within the scopeof this disclosure to slidably couple an actuator (such as actuator 120)to a housing (such as housing 110). Configurations wherein the actuator120 is manipulated through rotation, translation, or other displacementrelative to the housing 110 are all within the scope of this disclosure.

The actuator 120 comprises an input portion 121 extending from theaperture 122. In the depicted embodiment, the input portion 121comprises a surface, at least partially exposed with respect to thehousing 110. In operation, a user may manipulate the actuator 120 byexerting a force on the input portion 121, illustrated by the arrowlabeled “input” in FIG. 2, displacing the input portion 121 generallytoward the longitudinal axis of the deployment device (100 of FIG. 1)and causing the actuator 120 to rotate about the pin 112 with respect tothe housing 110. Displacement of the actuator 120 due to a force such asillustrated by the arrow labeled “input” corresponds to “depression” ofthe actuator 120 or “depression of the actuator 120 with respect to thehousing 110.”

The actuator 120 may further comprise a transfer arm 123 extending fromthe pin aperture 122. The transfer arm 123 may be rigidly coupled to theinput portion 121, including embodiments wherein both the transfer arm123 and the input portion 121 are integrally formed with the rest of theactuator 120. The transfer arm 123 extends to a ratchet slide engagingportion 124. Depression of the input portion 121, in the direction shownby the arrow labeled “input” displaces the transfer arm 123 as theactuator 120 is rotated about the pin 112.

Depression of the input portion 121 thus causes displacement of theratchet slide engaging portion 124 with respect to the housing 110. Thisdisplacement of the ratchet slide engaging portion 124 can be understoodas rotation about the pin 112 having a proximal translation componentand a vertical translation component, as rotation of the input portion121 in the direction indicated by the arrow labeled “input” willdisplace (with respect to the housing 110) the ratchet slide engagingportion 124 both proximally and vertically.

A spring 115 may be disposed between the actuator 120 and the housing110. The spring 115 may be configured to resist displacement of theactuator 120 in the direction indicated by the arrow labeled “input” andmay be configured to return the actuator to the relative position shownin FIG. 2 after it has been depressed by a user. When the handleassembly 102 is unconstrained, the spring 115 may thus maintain (orreturn to) the relative position of the actuator 120 with respect to thehousing 110 as shown in FIG. 2.

In the illustrated embodiment, the spring 115 engages with a springledge 125 of the actuator 120 and spring protrusions 111 of the housing110. The spring protrusions 111 may provide a bearing surface for thespring 115 offset from movable internal components of the handleassembly 102 (such as a carrier 140 further detailed below). Thoughthree spring protrusions 111 are shown in the depicted embodiment, moreor fewer protrusions, or use of other features such as ridges, ledges,shoulders, and so forth are within the scope of this disclosure.

The depicted embodiment comprises a leaf spring 115. Other biasingelements, such as coil springs, piston assemblies, compliant mechanisms,and so forth are likewise within the scope of this disclosure. In someinstances, a compliant portion of one or both of the housing 110 andactuator 120 may provide a biasing force analogous to that provided bythe spring 115. Leaf springs, such as spring 115, may be configured toprovide a relatively constant biasing force notwithstanding compressionof the spring 115 as the actuator 120 is rotated or depressed withrespect to the housing 110.

As the actuator 120 is depressed with respect to the housing 110, thespring 115 compresses and the ratchet slide engaging portion 124 isdisplaced as described above. Again, the displacement of the ratchetslide engaging portion 124 with respect to the housing 110 can beunderstood as having a proximal component and a vertical component.

The ratchet slide engaging portion 124 may be operably coupled to aratchet slide 130 such that displacement of the ratchet slide engagingportion 124 likewise displaces the ratchet slide 130. The ratchet slide130 may be constrained such that the ratchet slide 130 is configuredonly for proximal or distal displacement with respect to the housing110. Thus, operable coupling of the ratchet slide engaging portion 124to the ratchet slide 130 may allow for sliding interaction between theratchet slide engaging portion 124 and the ratchet slide 130 such thatonly the proximal or distal component of the displacement of the ratchetslide engaging portion 124 is transferred to the ratchet slide 130.Stated another way, the ratchet slide 130 may be displaced in adirection parallel to the longitudinal axis of the deployment device 100while the input displacement may be at an angle to the longitudinal axisof the deployment device 100. It is noted that, in the configurationshown in FIG. 2, a safety member 180 may prevent proximal displacementof the ratchet slide 130. The safety member 180, including removalthereof, is discussed in more detail below. Discussion herein relatingto displacement of the ratchet slide 130 and related components may thusbe understood as disclosure relevant to a configuration of the handleassembly 102 in which the safety member 180 has been removed.

As the actuator 120 is depressed with respect to the housing 110, theratchet slide 130 may thus be proximally displaced with respect to thehousing 110. One or both of the ratchet slide 130 and actuator 120 mayalso interact with the housing 110 such that there is a positive stop toarrest the depression of the actuator 120 and/or proximal displacementof the ratchet slide 130. This positive stop may be an engaging ledge,shoulder, lug, detent, or other feature coupled to the housing 110,including features integrally formed on the housing 110.

A full stroke of the actuator 120 may thus correspond to displacementfrom the unconstrained position shown in FIG. 2, to the positive stopcaused by interaction with the housing 110 when the actuator 120 isdepressed. Release of the actuator 120 following a full or a partialstroke may then result in a return of the actuator 120 to theunconstrained state, due to the biasing force provided by the spring115. The unconstrained state shown in FIG. 2 refers to lack ofconstraint due to user input. In this state, the spring 115 may bepartially compressed, and interaction between the actuator 120 and thehousing 110 may prevent rotation of the actuator 120 about the pin 112in the opposite direction to depression of the actuator 120, or thereturn direction. In other words, interaction between the actuator 120and the housing 110 (or features of the housing 110) may create apositive stop to the return motion of the actuator 120 as well.

Referring to both FIGS. 1 and 2, the actuator 120 and the housing 110may be coupled such that pinching of external materials (such as apractitioner's hand or a surgical drape) is minimized when the actuator120 is depressed or returned. For instance, the actuator 120 maycomprise a shell configured to mate with, and slide into, the housing110. Though the components may slide and rotate with respect to eachother, the interface of the components may be sufficiently close and/orsmooth to minimize pinching or other engagement of external materials.This close and/or smooth interface may refer to interaction at the edgesof the actuator 120 as it is displaced into the housing 110 and/or tointeraction at the portion of the actuator 120 near the pin 112, as theactuator 120 returns to the unconstrained position.

As also shown in FIGS. 1 and 2, the input portion 121 of the actuator120 may also comprise ridges or other features to facilitate handling orgripping of the actuator 120 during use.

Referring again to FIG. 2, the ratchet slide 130 may thus be proximallydisplaced during depression of the actuator 120. Again, suchdisplacement may correspond to a configuration in which the safetymember 180 shown in FIG. 2 has been removed. Proximal displacement ofthe ratchet slide 130 may also proximally displace the carrier 140 dueto interaction between one or more carrier engaging ratchet lugs 136 onthe ratchet slide 130 and a ratchet slide engaging arm 146 coupled tothe carrier 140.

FIG. 3A is a perspective view of the ratchet slide 130 of the deploymentdevice 100 of FIGS. 1 and 2. FIG. 3B is a cross-sectional view of theratchet slide 130 of FIG. 3A, taken through a vertical plane disposedalong a longitudinal centerline of the ratchet slide 130. When theratchet slide 130 is disposed within the handle assembly 102 of FIG. 2,this cross-sectional plane would intersect the longitudinal axis of thedeployment device 100.

As shown in FIGS. 2, 3A, and 3B, the ratchet slide 130 may comprise aplurality of carrier engaging ratchet lugs 136. The carrier engagingratchet lugs 136 may be spaced at even intervals along the longitudinaldirection of the ratchet slide 130. In the figures, exemplary carrierengaging ratchet lugs are denoted with reference numeral 136, while thedistal most carrier engaging ratchet lug, disposed at the distal end ofthe ratchet slide 130 is denoted with reference numeral 136 a.

The ratchet slide 130 further comprises a ratchet slide safety opening139 and an actuator engaging opening 134. These features are discussedin more detail below.

As noted above, interaction between the ratchet slide engaging portion124 of the actuator 120 and the ratchet slide 130 may proximallydisplace the ratchet slide 130 with respect to the housing 110.Engagement between the carrier 140 and one of the carrier engagingratchet lugs 136 may also proximally displace the carrier 140 as theratchet slide 130 is proximally displaced with respect to the housing110. In the configuration of FIG. 2, the ratchet slide engaging arm 146of the carrier 140 is engaged with the distal most carrier engagingratchet lug 136 a.

FIG. 4 is a side view of the carrier 140 of the deployment device 100 ofFIGS. 1 and 2. As shown in FIG. 4, the ratchet slide engaging arm 146extends radially away from a longitudinal axis of the carrier 140. Whenthe carrier 140 is disposed within the handle assembly 102 of FIG. 2,the longitudinal axis of the carrier 140 is disposed along thelongitudinal axis of the deployment device 100.

FIG. 5 is a cross-sectional view of a portion of the deployment device100 shown in FIGS. 1 and 2. Specifically, the actuator 120, ratchetslide 130, and carrier 140 are shown in FIG. 5, in the same relativepositions, and along the same cross-sectional plane as in FIG. 2.

Referring to FIGS. 2-5, during depression of the actuator 120 withrespect to the housing 110, the actuator 120 rotates around the pinaperture 122. This rotation causes displacement of the ratchet slideengaging portion 124 of the actuator 120. The component of thisdisplacement correlating to proximal displacement of the ratchet slideengaging portion 124 also proximally translates the ratchet slide 130due to interaction between the ratchet slide engaging portion 124 of theactuator 120 and the actuator engaging opening 134 of the ratchet slide130. Stated another way, the walls or faces that define the actuatorengaging opening 134 may contact the ratchet slide engaging portion 124such that the ratchet slide 130 is displaced when the actuator 120 isdisplaced.

Proximal displacement of the ratchet slide 130 also proximally displacesthe carrier 140 due to interaction between the carrier engaging ratchetlugs 136 and the ratchet slide engaging arm 146. In the depictedembodiment, a distal surface of the ratchet slide engaging arm 146 is incontact with a proximal face of the distal most carrier engaging ratchetlug 136 a. This contact exerts proximal force on the distal surface ofthe ratchet slide engaging arm 146, displacing the carrier 140 in aproximal direction. Accordingly, the ratchet slide 130 and carrier 140will move proximally until the actuator 120 reaches the end of thestroke.

FIG. 6 is a cross-sectional view of the housing 110 and the carrier 140in the same relative positions shown in FIG. 2. The cross-sectionalplane of FIG. 6 extends along the longitudinal axis of the deploymentdevice; however, the cross-sectional plane of FIG. 6 extendshorizontally, orthogonal to the cross-sectional planes of FIGS. 2, 3B,and 5.

As shown in FIG. 6, the carrier 140 comprises a housing engaging arm 148extending radially away from a longitudinal axis of the carrier 140. Thehousing 110 comprises a plurality of carrier engaging housing lugs 118.In FIG. 6, exemplary carrier engaging housing lugs are denoted byreference numeral 118, with the distal most carrier engaging housing lugdenoted by reference numeral 118 a.

Referring to FIGS. 2-6, as interaction between the actuator 120, ratchetslide 130, and carrier 140 displaces the carrier 140 with respect to thehousing 110 (as shown and described above), the housing engaging arm 148(shown in FIG. 6) of the carrier 140 will deflect radially inward due tocontact with one of the carrier engaging housing lugs 118. For example,from the position shown in FIG. 6, as interaction between the distalmost carrier engaging ratchet lug 136 a and the ratchet slide engagingarm 146 of the carrier 140 draws the carrier 140 proximally, the distalmost carrier engaging housing lug 118 a causes the housing engaging arm148 to displace radially inward. The housing engaging arm 148 willcontinue to deflect radially inward until the distal end of the housingengaging arm 148 is positioned proximal of the distal most carrierengaging housing lug 118 a, at which point the housing engaging arm 148will return to the radially outward configuration shown in FIG. 6. Thepoint at which the housing engaging arm 148 moves proximally of thedistal most carrier engaging housing lug 118 a, may correspond to thestroke of the actuator 120, such that engagement between the housingengaging arm 148 and the next carrier engaging housing lug 118 (movingin a proximal direction) occurs at the end of the stroke, which maycorrespond to contact between the ratchet slide 130 and/or actuator 120and a positive stop on the housing 110 defining the end of the stroke.

As the actuator 120 is released following the stroke, interactionbetween the spring 115, the housing 110, and the actuator 120 willreturn the actuator 120 to the unconstrained position (the positionshown in FIG. 2) as discussed above. Corresponding rotation of theactuator 120 about the pin aperture 122 will thus correlate todisplacement of the ratchet slide engaging portion 124, including acomponent of displacement in the distal direction. Interaction betweenthe ratchet slide engaging portion 124 and the actuator engaging opening134 will then correlate to distal displacement of the ratchet slide 130.Thus, when the actuator 120 is released at the end of a stroke, theactuator 120, the spring 115, and the ratchet slide 130 return to thesame positions relative to the housing as shown in FIG. 2.

As the actuator 120 returns to the unconstrained position, however,interaction between the housing engaging arm 148 and the carrierengaging housing lug 118 prevents distal displacement of the carrier140. Specifically, the distal surface of the housing engaging arm 148will be in contact with a proximal facing surface of a carrier engaginghousing lug 118, the interaction preventing the carrier 140 fromreturning to the pre-stroke position. In the exemplary stroke discussedabove, the distal most carrier engaging housing lug 118 a displaced thehousing engaging arm 148 during the stroke, and the housing engaging arm148 engaged with the distal most carrier engaging housing lug 118 afollowing the stroke. Subsequent strokes move the carrier 140 along theplurality of carrier engaging housing lugs 118 in a proximal direction.

As the actuator 120 returns to the unconstrained state, radially inwarddisplacement of the ratchet slide engaging arm 146 of the carrier 140allows the ratchet slide 130 to move distally with respect to thecarrier 140, as engagement between the carrier 140 and the carrierengaging housing lugs 118 arrest distal displacement of the carrier 140.

Referring to FIGS. 2-6, with particular reference to the view of FIG. 5,distal displacement of the ratchet slide 130 with respect to the carrier140 creates interaction between the carrier engaging ratchet lugs 136and the ratchet slide engaging arm 146 causing the ratchet slideengaging arm 146 to displace radially inward. The proximal facingsurface of the carrier engaging ratchet lugs 136 may be angled tofacilitate this interaction. In the exemplary stroke discussed above,engagement between the distal most carrier engaging ratchet lug 136 adisplaced the carrier 140 in a proximal direction; during the return ofthe actuator 120, the next carrier engaging ratchet lug 136 (in aproximal direction) causes the radially inward displacement of theratchet slide engaging arm 146 until the ratchet slide engaging arm 146is proximal of the carrier engaging ratchet lug 136. At that point theratchet slide engaging arm 146 returns to a radially outward position(analogous to that shown in FIG. 5) though the distal surface of theratchet slide engaging arm 146 is now engaged with a proximal face ofthe next carrier engaging ratchet lug 136 (again in a proximaldirection). Displacement of the ratchet slide 130 sufficient to move toengagement with a subsequent carrier engaging ratchet lug 136 maycorrespond with the magnitude of ratchet slide 130 displacementcorresponding to a return of the actuator 120. Subsequent returns of theactuator 120 following strokes move the ratchet slide 130 such that theplurality of carrier engaging ratchet lugs 136 may serially engage thecarrier 140, stroke after stroke.

Accordingly, as described above, depressing the actuator 120 for a fullstroke, then allowing the actuator 120 to return to the unconstrainedposition, displaces the carrier 140 with respect to the housing 110 indiscrete increments, corresponding to the distance between adjacentcarrier engaging housing lugs 118 along the longitudinal direction.Interaction of the actuator 120 and positive stops associated with thehousing 110, carrier arms (e.g., ratchet slide engaging arm 146 andhousing engaging arm 148), and lugs (e.g., carrier engaging housing lugs118 and carrier engaging ratchet lugs 136) may also combine to give auser tactile and audible feedback as the carrier 140 is incrementallydisplaced. Further, one or more opening in the housing 110 may allow auser to observe the relative position of the carrier 140 providingfurther feedback as to carrier 140 position.

As detailed below, the relative position of the carrier 140 with respectto the housing 110 may correlate to the degree of deployment of a stentfrom the deployment device 100. Thus, visual, audible, and tactilefeedback as to the position of the carrier 140 provides a user withinformation regarding stent deployment during use of the deploymentdevice 100. This information may correlate to increased control duringdeployment as the practitioner quickly and intuitively can surmise thedegree of stent deployment.

As outlined above, tactile and/or audible feedback result from theinteractions of the carrier 140, ratchet slide 130, housing 110, and/oractuator 120. For example, as the ratchet slide engaging arm 146 orhousing engaging arm 148 of the carrier 140 deflects radially inwardthen return outward, there may be an audible and/or tactile response.

The device may be configured for visual feedback of, or relating to, therelative deployment of a stent. For example, in some embodiments, thehousing 110 may comprise viewing windows to allow a practitioner toobserve the position of the carrier 140 relative to the housing 110.Further, indicia on the housing 110 may correlate the position of thecarrier 140 to the degree of deployment of a stent.

The increments of displacement of the carrier 140 may correlate tostandard stent lengths or units of measure. For example, many stents aresized in 1 cm increments. Configuration of the increments ofdisplacement on the carrier 140 in 1 cm increments would thus directlycorrelate with stent length at a 1:1 ratio. Any other ratio, includingembodiment wherein a stroke correlates to a greater length (such as 2,3, 4, or 5 cm) or a lesser length (such as 0.01, 0.1, 0.25, 0.5, or 0.75cm) are likewise within the scope of this disclosure.

In some embodiments, interaction between the carrier 140, the ratchetslide 130, the housing 110, and/or the actuator 120 may compriseadditional carrier engaging ratchet lugs 136 and/or carrier engaginghousing lugs 118. For example, the carrier engaging ratchet lugs 136 maybe spaced to enable semi-continuous ratcheting of the ratchet slide 130with respect to the actuator 120 and/or the housing 110. Such anembodiment is described in further detail below in reference to thedeployment device 400 depicted in FIGS. 14-19.

The deployment device 100 may be configured as a universal deviceoperable with various stent lengths. In some embodiments a practitionermay directly equate the number of strokes needed to deploy a stent withthe length of the stent loaded in the deployment device 100 (such asfour strokes for a four centimeter stent). Further, a single design ofdeployment device 100 may be utilized with various lengths of stents,with a maximum length related to the maximum length of travel of thecarrier 140.

The nature of depression of the actuator 120 may facilitate one-handedoperation and may be ergonomically designed. First, a practitioner needonly grip the deployment device with one hand to depress the actuator,leaving a second hand free for other therapy needs. Further, thedirection with which the deployment device is gripped, with thepractitioner's hand extending laterally away from the longitudinal axisof the deployment device and the lateral direction of depression, asopposed, for example, to longitudinal gripping to actuate, may beergonomically desirable. Lateral gripping and input may more readilypresent the deployment device 100 for use when the delivery catheterassembly 104 is disposed within a patient's body, not requiring thepractitioner to move to an awkward stance with respect to other therapytools. Further, the input portion 121 of the actuator 120 may provideadditional surface for a practitioner to grip, facilitating use of agreater portion of a practitioner's hand for actuation, as compared to afinger trigger or similar actuation mechanism.

The incremental displacement of the carrier 140 may further facilitatepartial deployment of a stent, allowing a practitioner to deploy thestent in increments, potentially adjusting or confirming the position ofthe stent between these increments.

Still further, the deployment device 100 may be configured for use witheither the right or left hand, or gripped with the fingers or palm incontact with the actuator 120 without changing the design of thedeployment device 100. These features may further increase user comfortand control. Viewing windows in the housing 110 to confirm the positionon the carrier 140 may be located on one or both sides of the housing110 and may be associated with indicia correlating to stent length orother factors.

Moreover, the relative lengths of the input portion 121 and transfer arm123 of the actuator 120 may be configured to provide mechanicaladvantage when deploying a stent. This may increase comfort and controlduring use. The ratio of the length of the input portion 121—from itsdistal end to the pin aperture 122—to the length of the transfer arm123—from the pin aperture 122 to the ratchet slide engaging portion124—may be greater than or equal to 1.5:1, including 2:1, 2.5:1, 3:1,3.5:1 or greater. This ratio correlates to the mechanical advantageprovided by the device. In some instances the mechanical advantageprovided may be 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or greater. Stated anotherway, the ratio of length of travel of the input portion 121 to thecorresponding length of travel of the ratchet slide engaging portion 124may be 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or greater. Accordingly, the inputforce applied against the input portion 121 may result in a greaterforce exerted by the ratchet slide engaging portion 124 on the ratchetslide 130. The ratio of the force exerted on the ratchet slide 130 tothe input force may be 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or greater.

FIG. 7 is a front view of the deployment device 100, illustrating twocross-sectional planes. Specifically, plane A-A extends vertically alongthe longitudinal axis of the deployment device 100 viewing the exposedcomponents in a right to left direction. Plane A-A corresponds to thecross-sectional plane of FIGS. 2, 3B, and 5. Plane B-B also extends fromthe longitudinal axis of the deployment device 100, though Plane B-Bextends horizontally therefrom. Plane B-B corresponds to thecross-sectional plane of FIG. 6, and is viewed from a top to bottomdirection. The longitudinal axis of the deployment device 100 is in bothplanes A-A and B-B, with the line defined as the intersection betweenthese planes being the same line as the longitudinal axis as referencedherein.

Additionally, as stated above, the deployment device 100 may comprise asafety member 180. FIG. 8 is a perspective view of the safety member 180of the deployment device 100. The safety member 180 may be configuredwith a circular or partially circular opening configured to snap onto anoutside surface of a portion of the deployment device 100. Referring toboth FIG. 2 and FIG. 8, the safety member 180 may comprise a safety lug189 that extends through a ratchet slide safety opening (139 of FIG. 3A)and a similar safety opening in the housing 110 (not shown). When thesafety lug 189 is disposed within these openings, the safety lug 189 mayprevent proximal displacement of the carrier 140 and the ratchet slide130, thus preventing inadvertent deployment of a stent. A practitionermay leave the safety member 180 in place during displacement of thedelivery catheter assembly 104 to a treatment region. Due tointeractions between the carrier 140, ratchet slide 130, and actuator120, the safety member 180 likewise prevents displacement of theactuator 120 when the safety lug 189 extends through the openings.

In the depicted embodiment, the safety lug 189 extends through a bottomportion of the housing 110 and ratchet slide 130. In other embodiments,the safety lug 189 may extend through a top surface of the housing 110,interacting with the carrier 140 but not directly with the ratchet slide130. Nevertheless, prevention of proximal displacement on the carrier140 only, will also prevent displacement of the ratchet slide 130 andthe actuator 120 due to the interaction between these elements.

In some embodiments, the safety member 180 may be tethered to thedeployment device 100, or may comprise a sliding switch or other elementoperably coupled to the housing 110 or other components of thedeployment device 100. In the depicted embodiment, the safety member 180is removably coupled.

FIG. 9 is a side view of a portion of the delivery catheter assembly 104of the deployment device 100. Specifically, FIG. 9 is a side view of adistal section of the delivery catheter assembly 104. FIG. 10 is a sideview of the same longitudinal section of the delivery catheter assembly104 as shown in FIG. 9; however, the outer sheath (150 of FIG. 9) hasbeen removed to show other components.

Referring to FIGS. 1, 2, 9, and 10, the delivery catheter assembly 104may be configured to deploy a stent as the deployment device 100 ismanipulated, as discussed above. The delivery catheter assembly 104 maycomprise an outer sheath 150, extending from the handle assembly 102.The outer sheath 150 may be fixedly coupled to the carrier 140. Thedelivery catheter assembly 104 may further comprise an intermediatesheath 160 and an inner sheath 170, both disposed within the outersheath 150, and both fixedly coupled to the housing 110. Thus, proximaldisplacement of the carrier 140 with respect to the housing 110 willproximally displace the outer sheath 150 with respect to both theintermediate sheath 160 and the inner sheath 170.

The outer sheath 150 may comprise a shaft section 156 extending from thecarrier 140 in a distal direction. At the distal end of the shaftsection 156 the outer sheath 150 may comprise a flex zone 154 extendingfrom the shaft section 156 in a distal direction. Finally, the outersheath 150 may comprise a pod 152 extending from the flex zone 154 in adistal direction. (As shown in FIG. 9, the pod 152 may be transparent.)

The shaft section 156 of the outer sheath 150 may have a differentstiffness and/or durometer than the flex zone 154 and/or the pod 152.The flexibility toward the distal end of the outer sheath 150 mayimprove trackability of the delivery catheter assembly 104 over aguidewire and may be less traumatic, while a stiffer shaft may be morekink resistant and/or transmit displacement and/or torque along theshaft section 156.

The pod 152 may be configured to retain a crimped or otherwiseconstrained stent. Removal of the pod 152 from the stent may allow thestent to self-expand, and thereby deploy. It is within the scope of thisdisclosure for the pod 152 to be any relative length, the flex zone 154to be any relative length, and the shaft section 156 to be any relativelength. Thus, in some instances, a constrained stent may be in one, two,or all three of these portions of the outer sheath 150. For example, inthe illustrated embodiment, an annular space 176 (described furtherbelow) is configured to receive a crimped stent extending along the pod152 as well as portions of the flex zone 154 and shaft section 156. Inother embodiments, the annular space 176 may correlate just to the pod152 segment, meaning the device is configured to retain a crimped stentonly within the pod 152 segment.

The distal tip 174 of the delivery catheter assembly 104 may be coupledto and/or integrally formed with the inner sheath 170. A lumen 172 mayextend along the inner sheath 170 from the proximal end of thedeployment device 100 to the distal tip 174. A luer fitting 113 coupledto the housing 110 may be in communication with the lumen 172. Aguidewire may thus extend through the luer fitting 113, through thelumen 172, and out of the distal tip 174. Further, fluid introduced intothe luer fitting 113 may be utilized to flush the lumen 172.

The inner sheath 170 may be fixed to the housing, for example, at theproximal end of the inner sheath 170. An intermediate sheath 160, alsofixed to the housing 110, may extend over a portion of the inner sheath170. The intermediate sheath 160 and inner sheath 170 may or may not bedirectly fixed to each other. In some embodiments, the intermediatesheath 160 may be a close slip fit over the inner sheath 170.

The inner sheath 170 extends distally beyond a distal end of theintermediate sheath 160, creating an annular space 176 between the innersheath 170 and the outer sheath 150 adjacent the distal tip 174,extending proximally to the distal end of the intermediate sheath 160.This annular space 176 may be configured to retain a crimped stent.

As the deployment device 100 is manipulated to incrementally displacethe carrier 140 with respect to the housing 110, the outer sheath 150 isincrementally displaced proximally with respect to the inner sheath 170and intermediate sheath 160. The distal end of the intermediate sheath160 interacts with the proximal end of the stent, preventing the stentfrom being drawn back with the outer sheath 150. Thus, the stent isincrementally exposed, and allowed to self-expand and deploy.

In some embodiments, a fluid aperture 162 in the intermediate sheath 160may extend through the wall of the intermediate sheath 160 and the wallof the inner sheath 170, into fluid communication with the inner lumen172. This fluid aperture 162 may thus provide fluid communicationbetween the annular space 176 and the inner lumen 172, as fluid withinthe inner lumen 172 can move through the fluid aperture 162 and into theannular space 176. This communication may be used to flush the annularspace 176 during use, which may be configured to remove air or otherunwanted materials in the annular space 176 or around the crimped stent.

The distal tip 174 may comprise a flexible material and may beconfigured to be atraumatic. The distal tip 174 may comprise nylons,including PEBAX® polyether block amides.

In some instances braided or coil reinforcements may be added to theouter sheath 150, the intermediate sheath 160, and/or the inner sheath170 to increase kink resistance and/or elongation. Reinforcing membersmay comprise stainless steel, nitinol, or other materials and may beround, flat, rectangular in cross section, and so forth.

One, two, or all of the outer sheath 150, the intermediate sheath 160,and/or the inner sheath 170 may be configured with varying durometers orother properties along the length thereof. In some instances the outersheath 150 may be configured with a proximal section with a durometerbetween 72 and 100 on the Shore D scale or may be greater than 100 onthe Shore D scale. A second portion of the outer sheath 150 may comprisea durometer of 63 on the Shore D scale, and a distal section with adurometer between 40 and 55 on the Shore D scale. Any of these values,or the limits of any of the ranges, may vary by 15 units in eitherdirection. In some instances the second portion will begin about sixinches from the distal end of the outer sheath 150, and the distalsection will begin about three inches from the distal end of the outersheath 150. These sections may or may not correspond to the shaftsection 156, the flex zone 154, and the pod 152 as described above. Theintermediate sheath 160 may be configured with varying durometer zoneswithin the same ranges of hardness and length.

Any of the inner sheath 170, intermediate sheath 160, and outer sheath150 may have differing durometer or flex zones along their lengths, andthese zones may overlap in various ways to create various stress/strainprofiles for the overall delivery catheter assembly 104. Overlapping ofsuch zones may reduce tendency to kink, including tendency to kink attransition zones. Further, the housing 110 may be coupled to a strainrelief member 116 (as shown in FIG. 2).

Any of the outer sheath 150, the intermediate sheath 160, and the innersheath 170 may be comprised of nylons, including PEBAX® polyether blockamides. Further, during manufacture, any of these members may beconfigured with a low friction outer surface, including through“frosting” the materials, by blowing air across the material duringextrusion, or by using additives during extrusion to reduce friction.

In some instances, during manufacture the distal tip 174 may be pulledinto interference with the outer sheath 150, prestressing the innersheath 170 in tension. This may reduce any effects of material creep orelongation during sterilization, keeping the distal tip 174 snuglynested with the outer sheath 150. Further, during manufacture, theinterface zone between the outer sheath 150 and the carrier 140 may beconfigured with a tolerance zone, meaning the outer sheath 150 can becoupled to the carrier 140 at multiple points along an inside diameterof the carrier 140. This tolerance may enable manufacturingdiscrepancies or variations to be taken up during assembly to ensure asnug nest between the distal tip 174 and the outer sheath 150. The sametolerance fit may be applied to the inner sheath 170 and/or theintermediate sheath 160 wherein these members couple to the housing 110,including a fit zone along an inside diameter of the luer fitting 113.

In some instances, the outer sheath 150 may include indicia correlatingto the degree to which a stent has been deployed. These indicia maycorrespond to the position of the outer sheath 150 with respect to thehousing 110. For example, as the outer sheath 150 is drawn into thehousing 110, different indicia are exposed and/or covered.

Further, in some instances, the deployment device 100 may be configuredsuch that the outer sheath 150 may be distally displaced after the stentis deployed to nest the distal tip 174 in the outer sheath 150 duringwithdrawal of the deployment device 100 from a patient. Suchconfigurations may include features of the handle assembly 102 thatdisengage the carrier 140 from one or more elements after stentdeployment.

FIGS. 11A-11D depict an embodiment of a deployment device 200 thatresembles the deployment device 100 described above in certain respects.Accordingly, like features are designated with like reference numerals,with the leading digits incremented to “2.” For example, the embodimentdepicted in FIGS. 11A-11D includes a distal tip 274 that may, in somerespects, resemble the distal tip 174 of FIGS. 1, 9, and 10. Relevantdisclosure set forth above regarding similarly identified features thusmay not be repeated hereafter. Moreover, specific features of thedeployment device 200 and related components shown in FIGS. 1-10 may notbe shown or identified by a reference numeral in the drawings orspecifically discussed in the written description that follows. However,such features may clearly be the same, or substantially the same, asfeatures depicted in other embodiments and/or described with respect tosuch embodiments. Accordingly, the relevant descriptions of suchfeatures apply equally to the features of the deployment device 200 andrelated components depicted in FIGS. 11A-11D. Any suitable combinationof the features, and variations of the same, described with respect tothe deployment device 100 and related components illustrated in FIGS.1-10, can be employed with the deployment device 200 and relatedcomponents of FIGS. 11A-11D, and vice versa. This pattern of disclosureapplies equally to further embodiments depicted in subsequent figuresand described hereafter, wherein the leading digits may be furtherincremented.

FIG. 11A is a perspective view of the deployment device 200. Thedeployment device 200 comprises a handle assembly 202 adjacent theproximal end of the deployment device 200. An elongate delivery catheterassembly 204 extends distally from the handle assembly 202 to the distaltip 274. The handle assembly 202 may provide a proximal user input, withone or more components configured to allow a practitioner to deploy orotherwise manipulate a prosthesis disposed within the delivery catheterassembly 204. As discussed above, though specific examples herein mayrefer to prostheses such as stents, other prostheses are also within thescope of this disclosure, including, but not limited to, vascularprostheses, stents, stent-grafts, shunts, grafts, and so forth.

FIG. 11B is a cross-sectional view of a portion of the delivery catheterassembly 204 of the deployment device 200 of FIG. 11A along plane11B-11B. Specifically, FIG. 11B is a cross-sectional view of a distalportion of the delivery catheter assembly 204. FIG. 11C is across-sectional view of a portion of the delivery catheter assembly 204of the deployment device 200 of FIG. 11A along plane 11C-11C. FIG. 11Dis a side view of the same longitudinal section of the delivery catheterassembly 204 as shown in FIG. 11B; however, the outer sheath (250 ofFIG. 11B) has been removed to show other components.

Referring to FIGS. 11B-11D, the delivery catheter assembly 204 maycomprise an outer sheath 250. The delivery catheter assembly 204 mayfurther comprise an intermediate sheath 260 and an inner sheath 270,each of which can be disposed within the outer sheath 250. Additionally,the inner sheath 270 can be disposed within the intermediate sheath 260.In certain embodiments, the delivery catheter assembly 204 may lack theintermediate sheath 260. In some embodiments, the outer sheath 250 maybe displaced with respect to each of the intermediate sheath 260 and theinner sheath 270.

An annular space 276 may be disposed between each of the outer sheath250 and the inner sheath 270. In certain embodiments, the annular space276, or a portion of the annular space 276, may be configured to receiveand/or retain a crimped or otherwise constrained stent. Removal ordisplacement of the outer sheath 250 from around the constrained stentmay allow the stent to self-expand, and thereby deploy. It is within thescope of this disclosure for the annular space 276 to be any relativelength. Thus, in some instances, a constrained stent may be disposedalong only a portion of a length of the annular space 276. In some otherinstances, a constrained stent may be disposed along substantially theentire length of the annular space 276.

In various embodiments, the intermediate sheath 260 may be directlycoupled to the inner sheath 270. In various other embodiments, theintermediate sheath 260 may not be directly coupled to the inner sheath270. For example, the intermediate sheath 260 may be a close slip fitover the inner sheath 270.

As depicted, the inner sheath 270 can extend distally beyond a distalend of the intermediate sheath 260, creating or forming the annularspace 276 between the inner sheath 270 and the outer sheath 250 adjacentthe distal tip 274. Furthermore, the annular space 276 may extendproximally from adjacent the distal tip 274 to adjacent the distal endof the intermediate sheath 260. The annular space 276 may be configuredto retain a crimped or constrained stent.

A pliant member 290 may partially surround or be disposed around theinner sheath 270. As shown, the pliant member 290 may be disposed arounda circumference of the inner sheath 270. For example, the pliant member290 may be coupled to a portion of an exterior surface of the innersheath 270. The pliant member 290 may also be disposed within a portionof the annular space 276. In some embodiments, the pliant member 290 maybe configured to engage and/or retain a stent or a constrained stent.Stated another way, the pliant member 290 may at least partially grip,anchor, hold, and/or grasp the stent or the constrained stent. Incertain embodiments, the stent may be disposed around the pliant member290 and then the stent may be constrained, crimped, and/or loaded aroundthe pliant member 290. Further, a portion of the loaded stent (e.g., aninner surface of the loaded stent) may imprint within a portion of thepliant member 290 (e.g., an outer surface of the pliant member 290) asdiscussed in further detail below.

In some embodiments, the pliant member 290 may comprise two or morelayers. In certain embodiments, the pliant member 290 may comprise twoor more materials. Each of the materials may have different or variousproperties, for example, variations in thickness, durometer, elasticity,etc. In certain embodiments, the pliant member 290 may comprise an innerlayer, wherein the inner layer is configured to adhere to or couple withthe inner sheath 270 (e.g., the inner layer may be designed for optimaladhesion to the inner sheath 270). Furthermore, the pliant member 290may comprise an outer layer, wherein the outer layer is configured tocomply or imprint with the stent or the constrained stent. For example,the inner layer of a pliant member may comprise a grafted polyolefin(e.g., OREVAC®), and an outer layer of the pliant member may comprise athermoplastic elastomer (e.g., CHRONOPRENE™). A portion of the innersheath 270 may be formed from a polyether block amide (e.g., PEBAX®),and the OREVAC® inner layer can couple with or form a bond with (e.g., astrong bond with) the PEBAX® inner sheath. Stated another way, theOREVAC® may be used as a tie layer between each of the PEBAX® and theCHRONOPRENE™.

In some embodiments, the pliant member 290 may be configured to limit orprevent longitudinal displacement of the constrained stent. For example,the pliant member 290 may grip the constrained stent such thatlongitudinal displacement of the constrained stent is limited orprevented. In certain embodiments, the pliant member 290 may beconfigured to limit or prevent the constrained stent from collapsing oraccordioning (e.g., longitudinally folding on itself). For example, thepliant member 290 may provide axial support to the constrained stent.Further, the pliant member 290 may be configured to partially surroundone or more portions of the constrained stent, meaning that the pliantmember 290 may conform to at least a portion of the constrained stent.For example, the pliant member 290 may conform to portions of the innersurface, shape, edges, and/or texture of the constrained stent.

The constrained stent (e.g., the inner surface of the constrained stent)may at least partially imprint around the pliant member 290. In someembodiments, imprinting of a helical stent (e.g., a stent having ahelical stent geometry) around the pliant member 290 may support rows ofcoils of the helical stent. Imprinting of the helical stent around thepliant member 290 may support each row of coils of the helical stent. Insome other embodiments, imprinting of a non-helical stent (e.g., a stenthaving a non-helical stent geometry) around the pliant member 290 maysupport rows of coils of the non-helical stent. Imprinting of thenon-helical stent around the pliant member 290 may support each row ofcoils of the non-helical stent.

In certain embodiments, the presence of the pliant member 290 mayincrease the force needed to proximally displace or pull back on theouter sheath 250. For example, disposition of the pliant member 290and/or a constrained stent within the annular space 276 may cause orform a tighter fit between each of the inner sheath 270 and the outersheath 250. However, due at least in part to the mechanical advantagethat can be provided by the deployment device, as discussed above, thestent can still be readily deployable by a user.

In various embodiments, the delivery catheter assembly 204 may becoupled to a deployment device including an actuator, wherein theactuator is analogous to the actuator 120. The actuator 120 can providea mechanical advantage to the deployment device. Furthermore, such amechanical advantage can assist a practitioner in using the deploymentdevice to deploy a stent that is disposed around the pliant member 290.

The pliant member 290 can be formed from one or more materials that areflexible, malleable, moldable, pliable, and/or supple. For example, thepliant member 290 may comprise one or more silicones, polyether blockamides (e.g., PEBAX®), thermoplastic elastomers (e.g., CHRONOPRENE™),and/or other suitable materials. As discussed above, the pliant member290 may be formed from multiple materials (e.g., the pliant member 290may include two or more layers). The pliant member 290 may be applied toor disposed on the inner sheath 270 using dip, spray, and/or reflowtechniques. Other suitable methods of applying or disposing the pliantmember 290 onto a surface (e.g., a surface of the inner sheath 270) arealso within the scope of this disclosure.

As illustrated, the pliant member 290 can extend longitudinally along aportion of the inner sheath 270 and/or through a portion of the annularspace 276. The pliant member 290 may have varying lengths. In someembodiments, the pliant member 290 may extend from adjacent a proximalend of the distal tip 274 to a position adjacent the distal end of theintermediate sheath 260. In some other embodiments, the pliant member290 may extend along only a portion of a longitudinal distance betweeneach of the proximal end of the distal tip 274 and the distal end of theintermediate sheath 260. As depicted, the distal end of the intermediatesheath can be disposed proximally of the pliant member 290.

The delivery catheter assembly 204 may be configured to receive and/orretain stents having varying lengths. In various embodiments, the pliantmember 290 may have a length that is greater than a length of the stent.In various other embodiments, the pliant member 290 may have a lengththat is substantially equal to the length of the stent. In various otherembodiments, the pliant member 290 may have a length that is less thanthe length of the stent.

In some embodiments, the pliant member 290 can be longitudinallycontinuous along the length of the stent. For example, the pliant member290 may extend longitudinally along the entire length of a constrainedstent. In certain embodiments, the pliant member 290 can becircumferentially continuous along an inside surface of the stent. Forexample, the pliant member 290 may extend along the entire innercircumference of a constrained stent.

The pliant member 290 may have varying durometers. In some embodiments,the durometer of the pliant member 290 may be about 10 to about 60 onthe Shore A scale, about 15 to about 45 on the Shore A scale, about 20to about 30 on the Shore A scale, about 23 to about 27 on the Shore Ascale, or another suitable durometer. In some other embodiments, thedurometer of the pliant member 290 may be about 25 on the Shore A scale.

The pliant member 290 may also a range of wall thicknesses (e.g., thedistance from an interior surface of the pliant member 290 to anexterior surface of the pliant member 290). In certain embodiments, thewall thickness of the pliant member 290 may be from about 0.0005 inch toabout 0.050 inch, including from about 0.001 inch to about 0.050 inch,or another suitable thickness.

In some embodiments, a compound or drug may be loaded in the pliantmember 290 and/or on an outer surface of the pliant member 290. Forexample, an anticoagulant drug may be loaded in and/or coated on thepliant member 290.

Analogous to the discussion above regarding the distal tip 174, thedistal tip 274 of the delivery sheath assembly 204 may be coupled toand/or integrally formed with the inner sheath 270. Furthermore, a lumen272 may extend along the inner sheath 270 from the proximal end of thedeployment device 200 to the distal tip 274.

In certain embodiments, the outer sheath 250 may be displaced orincrementally displaced proximally with respect to each of the innersheath 270 and the intermediate sheath 260. The distal end of theintermediate sheath 260 can engage or interact with the proximal end ofthe stent, limiting or preventing the stent from being drawn back withthe outer sheath 250. Thus, the stent can be incrementally exposed andallowed to self-expand and deploy.

As discussed above regarding the delivery catheter assembly 104, theouter sheath 250, the intermediate sheath 260, and/or the inner sheath270 may be configured with varying durometers or other properties alongthe length thereof.

FIG. 13A is a cross-sectional view of a portion of another embodiment ofa delivery catheter assembly 304. FIG. 13B is a side view of the portionof the delivery catheter assembly 304, wherein an outer sheath (350 ofFIG. 13A) has been removed to show other components. As illustrated, apliant member 390 may include a plurality of annular rings 392. Each ofthe annular rings 392 can be a discrete or separate annular ring. Insome embodiments, the annular rings 392 may be substantially evenlyspaced along a portion of a length of an inner sheath 370. In some otherembodiments, the annular rings 392 may be spaced in an uneven patternalong a portion of the length of the inner sheath 370. Stated anotherway, the annular rings 392 may be disposed in an intermittent manneralong a portion of the length of the inner sheath 370.

An annular ring 392 can partially surround or be disposed around theinner sheath 370. As shown, each of the annular rings 392 of the pliantmember 390 can be disposed around a circumference of the inner sheath370. For example, each of the annular rings 392 of the pliant member 390may be coupled to a portion of an exterior surface of the inner sheath370. In some embodiments, a subset of the annular rings 392 may fullysurround the inner sheath 370, and another subset of the annular rings392 may only partially surround the inner sheath 370.

Each of the annular rings 392 of the pliant member 390 may also bedisposed within a portion of an annular space 376. In some embodiments,one or more of the annular rings 392 of the pliant member 390 may beconfigured to engage and/or retain a stent or a constrained stent.Stated another way, one or more of the annular rings 392 of the pliantmember 390 may at least partially grip, anchor, hold, and/or grasp thestent or the constrained stent.

In certain embodiments, the stent may be disposed around a first annularring 392 disposed to align with a distal end portion of the stent, asecond annular ring 392 disposed to align with a middle portion of thestent, and/or a third annular ring 392 disposed to align with a proximalend portion of the stent. In certain other embodiments, a plurality ofannular rings 392 may be disposed to align with only one of the distalend portion, the middle portion, or the proximal end portion of thestent. Other configurations (i.e., dispositions) of the one or moreannular rings 392 in relation to a stent are also within the scope ofthis disclosure.

The stent may be constrained, crimped, and/or loaded around the one ormore annular rings 392 of the pliant member 390. Further, a portion ofthe loaded stent (e.g., an inner surface of the loaded stent) mayimprint within a portion of the one or more annular rings 392 of thepliant member 390 (e.g., an outer surface of the one or more annularrings 392 of the pliant member 390).

The constrained stent (e.g., the inner surface of the constrained stent)may at least partially imprint around the one or more annular rings 392of the pliant member 390. In some embodiments, imprinting of a helicalstent (e.g., a stent having a helical stent geometry) around the one ormore annular rings 392 of the pliant member 390 may support rows ofcoils of the helical stent. Imprinting of the helical stent around theone or more annular rings 392 of the pliant member 390 may support eachrow of coils of the helical stent. In some other embodiments, imprintingof a non-helical stent (e.g., a stent having a non-helical stentgeometry) around the one or more annular rings 392 of the pliant member390 may support rows of coils of the non-helical stent. Imprinting ofthe non-helical stent around the one or more annular rings 392 of thepliant member 390 may support each row of coils of the non-helicalstent.

As illustrated, the plurality of annular rings 392 of the pliant member390 can extend longitudinally along a portion of the inner sheath 370and/or through a portion of the annular space 376 (i.e., from theproximal-most annular ring 392 to the distal-most annular ring 392). Insome embodiments, the plurality of annular rings 392 of the pliantmember 390 may extend from adjacent a proximal end of a distal tip 374to a position adjacent the distal end of an intermediate sheath 360. Insome other embodiments, the plurality of annular rings 392 of the pliantmember 390 may extend along only a portion of a longitudinal distancebetween each of the proximal end of the distal tip 374 and the distalend of the intermediate sheath 360. As depicted, the distal end of theintermediate sheath 360 can be disposed proximally of the plurality ofannular rings 392 of the pliant member 390.

The delivery catheter assembly 304 may be configured to receive and/orretain stents having varying lengths. In various embodiments, theplurality of annular rings 392 of the pliant member 390 may have alength that is greater than a length of the stent (i.e., the length fromthe proximal-most annular ring 392 to the distal-most annular ring 392).In various other embodiments, the plurality of annular rings 392 of thepliant member 390 may have a length that is substantially equal to thelength of the stent. In various other embodiments, the plurality ofannular rings 392 of the pliant member 390 may have a length that isless than the length of the stent.

FIG. 12A is a side view of the distal portion of the delivery catheterassembly 204 of the deployment device 200 of FIG. 11A in a first state.FIGS. 12B and 12C are side views of the distal portion of the deliverycatheter assembly 204 in a second state and a third state, respectively.

With reference to FIG. 12A, a stent 35 may be constrained, crimped, ordisposed around the pliant member 290 and/or within the annular space276. In the first state, as illustrated, the outer sheath 250 may bedisposed over the stent 35 such that the stent 35 is in a constrainedconfiguration. The constrained stent 35 can extend from the proximal endof the distal tip 274 along only a portion of the pliant member 290,such that a gap or space is present along the pliant member 290 (e.g.,between a proximal end of the constrained stent 35 and the distal end ofthe intermediate sheath 260). In some embodiments, the constrained stent35 may extend along substantially an entire length of the pliant member290. In some other embodiments, the constrained stent 35 may be longerthan the pliant member 290. For example, in some instances, only aportion of the constrained stent 35 is disposed in the pliant member290.

FIG. 12B depicts the distal portion of the delivery catheter assembly204 in the second state. As illustrated, the distal portion of thedelivery catheter assembly 204 can be disposed within a vessel 45 (e.g.,a vessel of a patient). To deploy the stent 35, the outer sheath 250 maybe displaced proximally in relationship to the intermediate sheath 260,the inner sheath 270, and/or the pliant member 290. For clarity, thepattern depicted on the pliant member 290 in FIGS. 12B and 12C differsin certain respects, for example, from the pattern depicted on thepliant member 290 in FIG. 11D. The disclosure herein directed to thepliant member 290 of FIGS. 12B and 12C, however, is relevant to thepliant member 290 of FIG. 11D, and vice versa. In some embodiments, theouter sheath 250, the intermediate sheath 260, and/or the inner sheath270 may be operably coupled to an actuator, as discussed above inreference to deployment device 100. In some other embodiments, the outersheath 250, the intermediate sheath 260, and/or the inner sheath 270 maybe operably coupled to a housing, as discussed above in reference todeployment device 100, and the housing may be operably coupled to theactuator.

Furthermore, displacement of the actuator may be configured to displacethe outer sheath 250 relative to the inner sheath 270 and/or theintermediate sheath 260. As noted above, some embodiments of thedelivery catheter assembly 204 may lack an intermediate sheath 260.Proximal displacement of the outer sheath 250 may expose a portion ofthe constrained stent 35, and as such the stent 35 may at leastpartially deploy. For example, as portions of the pliant member 290 andthe constrained stent 35 are disposed distally of the distal end of theouter sheath 250, a distal portion of the stent 35 may expand radiallyaway from the pliant member 290 and partially deploy.

In certain embodiments, as noted above, the deployment device and/or theactuator may be configured to incrementally deploy the stent 35. Forexample, the outer sheath 250 may be configured to be proximallydisplaced relative to the inner sheath 270, the pliant member 290, andthe constrained stent 35 in a step-wise or incremental manner. Invarious embodiments, the pliant member 290 may aid or enhance thedeployment of the stent 35. For example, the pliant member 290 may limitor prevent over-deployment of the stent 35 (e.g., “jumping” of the stent35 out of the delivery catheter assembly 204 and/or jumping of the stent35 off of the inner sheath 270) during deployment of the stent 35.Further, the pliant member 290 may enhance the accuracy of thedeployment of the stent 35, for example, by limiting or preventingover-deployment or jumping of the stent.

In certain embodiments, the pliant member 290 may grip or support aconstrained portion of the stent 35 such that the deployed portion ofthe stent 35 can be pushed and/or shortened during deployment of thestent 35. For example, the delivery catheter assembly 204 and/or thedeployment device 200 may be moved or manipulated such that a portion ofthe stent 35, which is at least partially disposed in the pliant member290, can be pushed and/or shortened during deployment of the stent 35.

In some embodiments, the delivery catheter assembly 204 may beconfigured to adjust a length of the stent 35 (e.g., the stent 35 may beshortened) during deployment of the stent 35 such that a user may selecta length of the stent 35 (e.g., a custom length of the stent 35) basedon a characteristic such as patient anatomy. In certain embodiments, thedelivery catheter assembly 204 may have sufficient rigidity and/ordeployment control such that a user may push and/or pull the stent 35 tocontrol or determine the length of the stent 35 during deployment of thestent 35. In various embodiments, the pliant member 290 may beconfigured such that the stent 35 can remain in communication (e.g.,direct, physical communication) with the delivery catheter assembly 204and/or the deployment device 200 for the majority of the deployment ofthe stent 35.

In some embodiments, the stent may be configured to allow or permitnesting and/or telescoping of the rows of the stent. For example, thestent may comprise a plurality of rows, wherein each row of theplurality of rows is configured to be disposed around at least a portionof an outer surface of an adjacent row. Such a configuration may providea stent wherein an effective length of the stent can be adjusted duringdeployment of the stent by a user.

Upon deployment of a portion of the stent 35, the stent 35 (e.g., thedistal end of the stent 35) can be disposed against or engaged with awall 47 of the vessel 45 (see, e.g., FIG. 12B). Pushing or pulling onthe stent 35 via the deployment device 200 can compress the stent 35(i.e., reduce the distance between the coils of the stent 35) and/orstretch the stent 35 (i.e., increase the distance between the coils ofthe stent 35) along a portion of the stent 35 that is deployed but thatis not engaged with the wall 47. During such length adjustments, atleast a portion of the non-deployed portion of the stent 35 may beengaged by the pliant member 290. Such a configuration can provide apractitioner with enhanced flexibility during deployment of the stent35. For example, the practitioner can make adjustments (e.g., smalladjustments) to the length of the stent 35, for example, at or aroundbranch vessels or other structures within a patient. Without the pliantmember 290, the stent 35 may collapse or accordion within the deliverycatheter assembly 204 and/or the annular space 276 during an attemptedlength adjustment as described above.

FIG. 12C depicts the delivery catheter assembly 204 in the third state,wherein the distal end of the outer sheath 250 has been proximallydisplaced relative to the proximal end of the stent 35. Accordingly, inthe third state the stent 35 may fully deploy within the vessel 45. Insome embodiments, the stent 35 may deploy such that it engages orinteracts with the wall 47 of the vessel 45.

Methods of preparing or loading a deployment device 200 are disclosedherein. In some embodiments, the methods of preparing the deploymentdevice 200 can include obtaining a delivery catheter assembly 204. Thedelivery catheter assembly 204 can include an outer sheath 250 and aninner sheath 270, wherein the inner sheath 270 is disposed within theouter sheath 250.

In certain embodiments, the delivery catheter assembly 204 may furtherinclude an intermediate sheath 260, wherein the intermediate sheath 260is disposed between the outer sheath 250 and the inner sheath 260.Additionally, a distal end of the intermediate sheath 260 may bedisposed proximally of the distal end of the outer sheath 250 and thedistal end of the inner sheath 270.

In various embodiments, the methods of preparing the deployment device200 may include applying a pliant member 290 on at least a portion ofthe inner sheath 270. For example, the pliant member 290 may be appliedonto an outer surface of the inner sheath 250, and the pliant member 290may be coupled to the inner sheath 270. The pliant member 290 may beapplied to the inner sheath 270 by at least one of dipping, spraying,extrusion, reflowing, or another suitable technique.

As described above, the pliant member 290 may be configured to engageand/or retain a stent 35. Furthermore, a stent 35 may be disposed orpositioned around at least a portion of the pliant member 290, and thestent 35 may be constrained, crimped, or loaded within the pliant member290.

The methods of preparing the deployment device 200 may further includedisposing the outer sheath 250 over a portion of the stent 35. Such aconfiguration of the outer sheath 50 in relation to the stent 35 may aidin constraining the stent 35 within the pliant member 290. When thestent 35 is in the constrained configuration, a distal end of theintermediate sheath 260 may be disposed proximally of a proximal end ofthe pliant member 290.

Methods of deploying a stent 35 are also provided. In some embodiments,a delivery catheter assembly 204 may be obtained. The delivery catheterassembly 204 may comprise an outer sheath 250, an intermediate sheath260, and an inner sheath 270. Furthermore, a pliant member 290 cansurround a portion of the inner sheath 270. The methods of deploying thestent 35 may include positioning the stent 35 around the pliant member290 and/or constraining the stent 35 within the pliant member 290. Invarious embodiments, the outer sheath 250 may also be disposed over thestent 35 (e.g., such that the stent 35 is constrained within a portionof the pliant member 290).

In certain embodiments, methods of deploying the stent 35 may furtherinclude displacing an actuator, for example, an actuator that isoperably coupled to the delivery catheter assembly 204. Displacement ofthe actuator can be configured to proximally displace the outer sheath250 relative to each of the pliant member 290 and the constrained stent35 such that the stent 35 is partially deployed. As described above, theactuator may be configured to incrementally deploy the stent 35.Accordingly, methods of deploying the stent 35 can also includeadjusting the position of the partially deployed stent 35 after eachdisplacement of the actuator. The actuator can be displaced and/or theposition of the stent 35 adjusted until the stent 35 is fully deployed.As can be appreciated, each of the methods provided herein can also beadapted for use with the deployment device 100 and the componentsthereof.

FIG. 14 is a perspective view of a deployment device 400. The deploymentdevice 400 comprises a handle assembly 402 adjacent the proximal end ofthe deployment device 400. An elongate delivery catheter assembly 404extends distally from the handle assembly 402 to a distal tip ordelivery tip 474. The handle assembly 402 may provide a proximal userinput, with one or more components configured to allow a practitioner todeploy or otherwise manipulate a stent disposed within the deliverycatheter assembly 404.

As discussed above in reference to the deployment device 100, while inuse, the handle assembly 402 may be disposed outside of a patient'sbody, while the delivery catheter assembly 404 is advanced to atreatment location within the patient's body. As detailed below, a stentmay be disposed within a portion of the delivery catheter assembly 404such that a practitioner may deploy the stent from a distal end of thedelivery catheter assembly 404 through manipulation of one or morecomponents of the handle assembly 402.

FIG. 15 is a cross-sectional view of a portion of the deployment device400 of FIG. 14. Specifically, FIG. 15 is a side view of a portion of thedeployment device 400 of FIG. 14, taken through a cross-sectional planeextending vertically and intersecting a longitudinal axis of thedeployment device 400, when the deployment device 400 is positioned asshown in FIG. 14. The longitudinal axis of the deployment device 400extends along the center of the delivery catheter assembly 404,including along the center of components of the delivery catheterassembly 404 which overlap with the handle 402 assembly, such as anintermediate sheath 460, as shown in FIG. 15.

As the handle assembly 402 is configured to be grasped or otherwisemanipulated by a user and the delivery catheter assembly 404 isconfigured to extend to a treatment location within a patient's body,along the longitudinal axis, the delivery catheter assembly 404 extendsin a distal direction away from the handle assembly 402. The proximaldirection is opposite, correlating to a direction defined along thelongitudinal axis, extending from the distal tip 474 toward the handleassembly 402.

FIG. 15 depicts various internal components of the handle assembly 402,exposed by the cross-sectional view. A portion of the delivery catheterassembly 404 is also shown extending from the handle assembly 402. Thehandle assembly 402 comprises a housing 410. The housing 410 surroundscertain components of the handle assembly 402, as shown, providing agrip surface for a practitioner.

The actuator 420 is operably coupled to the housing 410. Manipulation ofthe actuator 420 with respect to the housing 410 may be configured todeploy the stent, as further detailed below. In the depicted embodiment,the actuator 420 is rotatably coupled to the housing 410 by a pin 412.The pin 412 extends from the housing 410 and may be integrally formedwith one or more other portions of the housing 410. As shown, the pin412 extends through a pin aperture 422 in the actuator 420. As discussedabove in reference to the actuator 120 and the housing 110, otherarrangements for operably coupling the actuator 420 and the housing 410are also within the scope of this disclosure.

The actuator 420 comprises an input portion 421 extending from the pinaperture 422. In the depicted embodiment, the input portion 421comprises a surface, at least partially exposed with respect to thehousing 410. In operation, a user may manipulate the actuator 420 byexerting a force on the input portion 421, illustrated by the arrowlabeled “input” in FIG. 15, displacing the input portion 421 generallytoward the longitudinal axis of the deployment device (400 of FIG. 14)and causing the actuator 420 to rotate about the pin 412 with respect tothe housing 410. Displacement of the actuator 420 due to a force such asillustrated by the arrow labeled “input” corresponds to “depression” ofthe actuator 420 or “depression of the actuator 420 with respect to thehousing 410.”

The actuator 420 may further comprise a transfer arm 423 extending fromthe pin aperture 422. The transfer arm 423 may be rigidly coupled to theinput portion 421, including embodiments wherein both the transfer arm423 and the input portion 421 are integrally formed with the rest of theactuator 420. The transfer arm 423 extends to a ratchet slide engagingportion 424. Depression of the input portion 421, in the direction shownby the arrow labeled “input,” displaces the transfer arm 423 as theactuator 420 is rotated about the pin 412.

Depression of the input portion 421 thus causes displacement of theratchet slide engaging portion 424 with respect to the housing 410. Thisdisplacement of the ratchet slide engaging portion 424 can be understoodas rotation about the pin 412 having a proximal translation componentand a vertical translation component, as rotation of the input portion421 in the direction indicated by the arrow labeled “input” willdisplace (with respect to the housing 410) the ratchet slide engagingportion 424 both proximally and vertically.

A spring 415 may be disposed between the actuator 420 and the housing410. The spring 415 may be configured to resist displacement of theactuator 420 in the direction indicated by the arrow labeled “input” andmay be configured to return the actuator 420 to the relative positionshown in FIG. 15 after it has been depressed by a user. When the handleassembly 402 is unconstrained, the spring 415 may thus maintain (orreturn to) the relative position of the actuator 420 with respect to thehandle 410 as shown in FIG. 15.

As the actuator 420 is depressed with respect to the housing 410, thespring 415 compresses and the ratchet slide engaging portion 424 isdisplaced as described above. Again, the displacement of the ratchetslide engaging portion 424 with respect to the housing 410 can beunderstood as having a proximal component and a vertical component.

The ratchet slide engaging portion 424 may be operably coupled to aratchet slide 430 such that displacement of the ratchet slide engagingportion 424 likewise displaces the ratchet slide 430. The ratchet slide430 may be constrained such that the ratchet slide 430 is configuredonly for proximal or distal displacement with respect to the housing410. Thus, operable coupling of the ratchet slide engaging portion 424to the ratchet slide 430 may allow for sliding interaction between theratchet slide engaging portion 424 and the ratchet slide 430 such thatonly the proximal or distal component of the displacement of the ratchetslide engaging portion 424 is transferred to the ratchet slide 430.Stated another way, the ratchet slide 430 may be displaced in adirection parallel to the longitudinal axis of the deployment device 400while the input displacement may be at an angle to the longitudinal axisof the deployment device 400. It is noted that, in the configurationshown in FIG. 15, a safety member 480 (similar to the safety member 180)may prevent proximal displacement of the ratchet slide 430. Discussionherein relating to displacement of the ratchet slide 430 and relatedcomponents may thus be understood as disclosure relevant to aconfiguration of the handle assembly 402 in which the safety member 480has been removed.

As the actuator 420 is depressed with respect to the housing 410, theratchet slide 430 may thus be proximally displaced with respect to thehousing 410. One or both of the ratchet slide 430 and actuator 420 mayalso interact with the housing 410 such that there is a positive stop toarrest the depression of the actuator 420 and/or proximal displacementof the ratchet slide 430. This positive stop may be an engaging ledge,shoulder, lug, detent, or other feature coupled to the housing 410,including features integrally formed on the housing 410. As depicted,the positive stop can be disposed proximally of a proximal end of theratchet slide 430. For example, the proximal end of the ratchet slide430 can interact with a portion of the housing 410 (e.g., a ledge,shoulder, etc.) disposed proximally of the proximal end of the ratchetslide 430. Accordingly, the handle assembly 402 may be configured suchthat the ratchet slide 430 is displaced or “travels” as much as possibleduring depression of the actuator 420.

A full stroke of the actuator 420 may thus correspond to displacementfrom the unconstrained position shown in FIG. 15, to the positive stopcaused by interaction with the housing 410 when the actuator 420 isdepressed. A partial stroke of the actuator 420 may correspond todisplacement from the unconstrained position shown in FIG. 15, to eachand/or any position prior to the positive stop caused by interactionwith the housing 410 when the actuator 420 is depressed. Release of theactuator 420 following a full stroke or a partial stroke may then resultin a return of the actuator 420 to the unconstrained state, due to thebiasing force provided by the spring 415. The unconstrained state shownin FIG. 15 refers to lack of constraint due to user input. In thisstate, the spring 415 may be partially compressed, and interactionbetween the actuator 420 and the housing 410 may prevent rotation of theactuator 420 about the pin 412 in the opposite direction to depressionof the actuator 420, or the return direction. In other words,interaction between the actuator 420 and the housing 410 (or features ofthe housing 410) may create a positive stop to the return motion of theactuator 420 as well.

With continued reference to FIG. 15, the ratchet slide 430 may thus beproximally displaced during depression of the actuator 420. Again, suchdisplacement may correspond to a configuration in which the safetymember 480 has been removed. Proximal displacement of the ratchet slide430 may also proximally displace a carrier 440 due to interactionbetween one or more carrier engaging ratchet lugs 436 on the ratchetslide 430 and a ratchet slide engaging arm 446 coupled to the carrier440. In some embodiments, the carrier 440 may be coupled to an outersheath 450. For example, the carrier 440 may be fixedly and/or rigidlycoupled to the outer sheath 450. In certain embodiments, an inner sheath470 may be coupled to the handle assembly 402. For example, the innersheath 470 may be fixedly and/or rigidly coupled to the handle assembly402.

FIG. 16A is a perspective view of the ratchet slide 430 of thedeployment device 400 of FIGS. 14 and 15. FIG. 16B is a cross-sectionalview of the ratchet slide 430 of FIG. 16A, taken through a verticalplane disposed along a longitudinal centerline of the ratchet slide 430.When the ratchet slide 430 is disposed within the handle assembly 402 ofFIG. 15, this cross-sectional plane would intersect the longitudinalaxis of the deployment device 400.

As shown in FIGS. 15, 16A, and 16B, the ratchet slide 430 may comprise aplurality of carrier engaging ratchet lugs 436. The carrier engagingratchet lugs 436 may be spaced at even intervals along the longitudinaldirection of the ratchet slide 430. As depicted, the plurality ofcarrier engaging ratchet lugs 436 may be disposed semi-continuously. Forexample, consecutive carrier engaging ratchet lugs 436 may be spacedabout 5 mm or less from each other, about 4 mm or less from each other,about 3 mm or less from each other, about 2 mm or less from each other,about 1 mm or less from each other, or any other suitable distance fromeach other. In the figures, exemplary carrier engaging ratchet lugs aredenoted with reference numeral 436, while the distal most carrierengaging ratchet lug, disposed at the distal end of the ratchet slide430, is denoted with reference numeral 436 a.

The ratchet slide 430 further comprises a ratchet slide safety opening439 (similar to the ratchet slide safety opening 139). The ratchet slide430 can further comprise an actuator engaging opening 434, which isdiscussed in more detail below.

As noted above, interaction between the ratchet slide engaging portion424 of the actuator 420 and the ratchet slide 430 may proximallydisplace the ratchet slide 430 with respect to the housing 410.Engagement between the carrier 440 and one of the carrier engagingratchet lugs 436 may also proximally displace the carrier 440 as theratchet slide 430 is proximally displaced with respect to the housing410. In the configuration of FIG. 15, the ratchet slide engaging arm 446of the carrier 440 is engaged with the distal most carrier engagingratchet lug 436 a.

FIG. 17 is a side view of the carrier 440 of the deployment device 400of FIGS. 14 and 15. As shown in FIG. 17, the ratchet slide engaging arm446 extends radially away from a longitudinal axis of the carrier 440.When the carrier 440 is disposed within the handle assembly 402 of FIG.15, the longitudinal axis of the carrier 440 is disposed along thelongitudinal axis of the deployment device 400.

As depicted, the ratchet slide engaging arm 446 comprises an angledportion or “toenail” portion 447 at a distal end of the ratchet slideengaging arm 446. As shown, the angled portion 447 extends radially awayfrom the longitudinal axis of the carrier 440 at a greater angle thanthe radial extension of the ratchet slide engaging arm 446 in relationto the longitudinal axis of the carrier 440. In some embodiments, theangled portion 447 can enhance engagement between the ratchet slideengaging arm 446 and a given carrier engaging ratchet lug 436 ascompared to a ratchet slide engaging arm lacking an angled portion. Forexample, due at least in part to the semi-continuous disposition of theplurality of the carrier engaging ratchet lugs 436 (as shown in FIGS.16A and 16B), the angled portion 447 of the ratchet slide engaging arm446 can allow or permit the ratchet slide engaging arm 446 to deflectradially adjacent to or against at least a portion of the ratchet slide430 at or adjacent the given carrier engaging ratchet lug 436. Theangled portion 447 can provide clearance for the ratchet slide engagingarm 446, allowing the angled portion to engage carrier engaging ratchetlugs 436 (even when closely spaced) without adjacent lugs interferingwith the position of the ratchet slide engaging arm 446 and preventingfull engagement.

FIG. 18 is a cross-sectional view of a portion of the deployment device400 shown in FIGS. 14 and 15. Specifically, the actuator 420, theratchet slide 430, and the carrier 440 are shown in FIG. 18, in the samerelative positions, and along the same cross-sectional plane as in FIG.15. FIG. 18A is a partial cut-away view of a portion of thecross-sectional view of FIG. 18. As shown, a portion of the ratchetslide 430 has been cut away in this view to show an engagement of theratchet slide engaging portion 424 with the actuator engaging opening434.

Referring to FIGS. 15-18A, during depression of the actuator 420 withrespect to the housing 410, the actuator 420 rotates around the pinaperture 422. This rotation causes displacement of the ratchet slideengaging portion 424 of the actuator 420. The component of thisdisplacement correlating to proximal displacement of the ratchet slideengaging portion 424 also proximally translates the ratchet slide 430due to interaction between the ratchet slide engaging portion 424 of theactuator 420 and the actuator engaging opening 434 of the ratchet slide430. Stated another way, the walls or faces that define the actuatorengaging opening 434 may contact the ratchet slide engaging portion 424such that the ratchet slide 430 is displaced when the actuator 420 isdisplaced.

Proximal displacement of the ratchet slide 430 also proximally displacesthe carrier 440 due to interaction between the carrier engaging ratchetlugs 436 and the ratchet slide engaging arm 446. In the depictedembodiment, a distal surface of the angled portion 447 of the ratchetslide engaging arm 446 is in contact with a proximal face of the distalmost carrier engaging ratchet lug 436 a. This contact exerts proximalforce on the distal surface of the angled portion 447 of the ratchetslide engaging arm 446, displacing the carrier 440 in a proximaldirection. Accordingly, the ratchet slide 430 and carrier 440 will moveproximally until the actuator 420 reaches the end of the stroke (e.g.,either a partial stroke or a full stroke).

FIG. 19 is a cross-sectional view of the housing 410 and the carrier 440in the same relative positions shown in FIG. 15. The cross-sectionalplane of FIG. 19 extends along the longitudinal axis of the deploymentdevice 400; however, the cross-sectional plane of FIG. 19 extendshorizontally, orthogonal to the cross-sectional planes of FIGS. 15, 16B,and 18.

As shown in FIG. 19, the carrier 440 comprises a housing engaging arm448 extending radially away from a longitudinal axis of the carrier 440.The housing 410 comprises a plurality of carrier engaging housing lugs418. In FIG. 19, exemplary carrier engaging housing lugs are denoted byreference numeral 418, with the distal most carrier engaging housing lugdenoted by reference numeral 418 a.

As depicted, the housing engaging arm 448 comprises an angled portion or“toenail” portion 449 at a distal end of the housing engaging arm 448.As shown, the angled portion 449 extends radially away from thelongitudinal axis of the carrier 440 at a greater angle than the radialextension of the housing engaging arm 448 in relation to thelongitudinal axis of the carrier 440. In some embodiments, the angledportion 449 can enhance engagement between the housing engaging arm 448and a given carrier engaging housing lug 418 as compared to a housingengaging arm lacking an angled portion. For example, due at least inpart to the semi-continuous disposition of the plurality of the carrierengaging housing lugs 418, the angled portion 449 of the housingengaging arm 448 can allow or permit the housing engaging arm 448 todeflect radially adjacent to or against at least a portion of theratchet slide 430 at or adjacent the given carrier engaging housing lug418. As with the angled portion 447 discussed above, the angled portion449 can provide clearance for the housing engagement arm 448, allowingthe angled portion 449 to engage carrier engaging housing lugs 418 (evenwhen closely spaced) without adjacent lugs interfering with the positionof the housing engagement arm 448 and preventing full engagement.

Referring to FIGS. 15-19, as interaction between the actuator 420,ratchet slide 430, and carrier 440 displaces the carrier 440 withrespect to the housing 410 (as shown and described above), the housingengaging arm 448 (shown in FIG. 19) of the carrier 440 will deflectradially inward due to contact with one of the carrier engaging housinglugs 418. For example, from the position shown in FIG. 19, asinteraction between the distal most carrier engaging ratchet lug 436 aand the ratchet slide engaging arm 446 of the carrier 440 draws thecarrier 440 proximally, the distal most carrier engaging housing lug 418a causes the housing engaging arm 448 to displace radially inward. Thehousing engaging arm 448 will continue to deflect radially inward untilthe distal end of the housing engaging arm 448 is positioned proximal ofthe distal most carrier engaging housing lug 418 a, at which point thehousing engaging arm 448 will return to the radially outwardconfiguration shown in FIG. 19. The point at which the housing engagingarm 448 moves proximally of the distal most carrier engaging housing lug418 a may correspond to the stroke of the actuator 420 (e.g., a partialstroke or a full stroke), such that engagement between the housingengaging arm 448 and the next carrier engaging housing lug 418 (movingin a proximal direction) occurs at the end of the stroke. In someembodiments, each carrier engaging housing lug 418 (or at least aportion of each of the carrier engaging housing lugs 418) may bedisposed such that a position of the carrier engaging housing lug 418corresponds to a position of a carrier engaging ratchet lug 436.

Further, a stroke of the actuator 420 can correspond to displacement ofthe carrier 440 past multiple carrier engaging housing lugs 418. Forclosely spaced carrier engaging housing lugs 418, the actuator 420 maythus be configured to displace the carrier 440 over a semi-continuousrange as the carrier 440 is advanced along the carrier housing engaginglugs 418. Partially depressing the actuator 420 may displace the carrier440 along and past the carrier engaging housing lugs 418, and uponrelease of the actuator 420, the carrier 440 may remain engaged with themost-recently passed carrier housing engaging lug 418. Thus, incrementsof displacement of the carrier 440 may correspond to the spacing thecarrier housing engaging lugs 418, rather than the length of the strokeof the actuator 420.

As the actuator 420 is released following the stroke, interactionbetween the spring 415, the housing 410, and the actuator 420 willreturn the actuator 420 to the unconstrained position (the positionshown in FIG. 15) as discussed above. Corresponding rotation of theactuator 420 about the pin aperture 422 will thus correlate todisplacement of the ratchet slide engaging portion 424, including acomponent of displacement in the distal direction. Interaction betweenthe ratchet slide engaging portion 424 and the actuator engaging opening434 will then correlate to distal displacement of the ratchet slide 430.Thus, when the actuator 420 is released at the end of a stroke, theactuator 420, the spring 415, and the ratchet slide 430 return to thesame positions relative to the housing 410 as shown in FIG. 15.

As the actuator 420 returns to the unconstrained position, however,interaction between the housing engaging arm 448 and the carrierengaging housing lug 418 prevents distal displacement of the carrier440. Specifically, the distal surface of the angled portion 449 of thehousing engaging arm 448 will be in contact with a proximal facingsurface of a carrier engaging housing lug 418, the interactionpreventing the carrier 440 from returning to the pre-stroke position. Inthe exemplary stroke discussed above, the distal most carrier engaginghousing lug 418 a displaced the housing engaging arm 448 during thestroke, and the housing engaging arm 448 engaged with the distal mostcarrier engaging housing lug 418 a following the stroke. Subsequentstrokes move the carrier 440 along the plurality of carrier engaginghousing lugs 418 in a proximal direction.

As the actuator 420 returns to the unconstrained state, radially inwarddisplacement of the ratchet slide engaging arm 446 of the carrier 440allows the ratchet slide 430 to move distally with respect to thecarrier 440, as engagement between the carrier 440 and the carrierengaging housing lugs 418 arrest distal displacement of the carrier 440.

Referring to FIGS. 15-19, with particular reference to the view of FIG.18, distal displacement of the ratchet slide 430 with respect to thecarrier 440 creates interaction between the carrier engaging ratchetlugs 436 and the angled portion 447 of the ratchet slide engaging arm446 causing the ratchet slide engaging arm 446 to displace radiallyinward. The proximal facing surface of the carrier engaging ratchet lugs436 may be angled to facilitate this interaction. During depression ofthe actuator 420, engagement between the distal most carrier engagingratchet lug 436 a can displace the carrier 440 in a proximal direction;during the return of the actuator 420, another carrier engaging ratchetlug 436 (in a proximal direction) can cause the radially inwarddisplacement of the ratchet slide engaging arm 446 until the angledportion 447 of the ratchet slide engaging arm 446 is proximal of thatcarrier engaging ratchet lug 436. At that point the ratchet slideengaging arm 446 returns to a radially outward position (analogous tothat shown in FIG. 18) though the distal surface of the angled portion447 of ratchet slide engaging arm 446 is now engaged with a proximalface of another carrier engaging ratchet lug 436 (again in a proximaldirection).

During a full stroke, engagement between a first carrier engagingratchet lug 436 can displace the carrier 440 in a proximal direction;during the return of the actuator 420, a plurality of the next carrierengaging ratchet lugs 436 (in a proximal direction) can cause aplurality of radially inward displacements of the ratchet slide engagingarm 446 as the angled portion 447 of the ratchet slide engaging arm 446moves proximally in relation to a plurality of the carrier engagingratchet lugs 436 during the full stroke. At that point the angledportion 447 of the ratchet slide engaging arm 446 returns to a radiallyoutward position (analogous to that shown in FIG. 18) though the distalsurface of the angled portion 447 of ratchet slide engaging arm 446 isnow engaged with a proximal face of a second carrier engaging ratchetlug 436 (again in a proximal direction). In such a configuration, aplurality of carrier engaging ratchet lugs 436 may be disposed betweenthe first carrier engaging ratchet lug 436 engaged during the stroke andthe second carrier engaging ratchet lug 436 engaged at the end of thatsame stroke. For example, 1, 2, 3, 4, 5, 6, or more carrier engagingratchet lugs 436 may be disposed between the first carrier engagingratchet lug 436 engaged during a single stroke and the second carrierengaging ratchet lug 436 engaged at the end of that single stroke.

Displacement of the ratchet slide 430 sufficient to move to engagementwith a subsequent carrier engaging ratchet lug 436 may correspond withthe magnitude of ratchet slide 430 displacement corresponding to areturn of the actuator 420. One return of the actuator 420 following atleast a partial stroke can move the ratchet slide 430 such that aplurality of carrier engaging ratchet lugs 436 may serially engage thecarrier 440 during the stroke.

Accordingly, as described above, depressing the actuator 420 for a fullstroke, then allowing the actuator 420 to return to the unconstrainedposition, displaces the carrier 440 with respect to the housing 410 indiscrete increments, corresponding to the distance between a pluralityof carrier engaging housing lugs 418 along the longitudinal direction.Depressing the actuator 420 for a partial stroke, then allowing theactuator 420 to return to the unconstrained position, can displace thecarrier 440 with respect to the housing 410 in discrete increments,corresponding to the distance between adjacent carrier engaging housinglugs 418 along the longitudinal direction.

As detailed below, the relative position of the carrier 440 with respectto the housing 410 may correlate to the degree of deployment of a stentfrom the deployment device 400. Thus, visual, audible, and tactilefeedback as to the position of the carrier 440 provides a user withinformation regarding stent deployment during use of the deploymentdevice 400. This information may correlate to increased control duringdeployment as the practitioner quickly and intuitively can surmise thedegree of stent deployment.

In some configurations, at least a portion of the elongate deliverycatheter assembly 404 may lengthen and/or stretch during use of thedeployment device 400. The configuration of the deployment device 400(e.g., comprising the semi-continuous disposition of the plurality ofthe carrier engaging ratchet lugs 436) can allow or permit more than oneincrement of displacement of the carrier 440 in relation to the ratchetslide 430. Furthermore, the configuration of the deployment device 400can allow or permit finely tuned deployment of the stent. For example,the stent can be deployed in about a 1 mm increment, about a 2 mmincrement, about a 3 mm increment, about a 4 mm increment, about a 5 mmincrement, or any other suitable increment.

The increments of displacement of the carrier 440 may be about 0.5 mm,about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 10 mm,about 25 mm, about 50 mm, about 100 mm, or any other suitable incrementof displacement. The incremental displacement of the carrier 440 mayfurther facilitate partial deployment of a stent, allowing apractitioner to deploy the stent in increments, potential adjusting orconfirming the position of the stent between these increments

Without further elaboration, it is believed that one skilled in the artcan use the preceding description to utilize the present disclosure toits fullest extent. The examples and embodiments disclosed herein are tobe construed as merely illustrative and exemplary and not a limitationof the scope of the present disclosure in any way. It will be apparentto those having skill in the art, and having the benefit of thisdisclosure, that changes may be made to the details of theabove-described embodiments without departing from the underlyingprinciples of the disclosure herein.

1. A prosthesis delivery catheter assembly, comprising: an outer sheath;an inner sheath disposed within the outer sheath, the inner sheathcomprising a first outer diameter; and a distal tip disposed at a distalend of the inner sheath, the distal tip comprising: a distal portion; aproximal portion; and a shoulder disposed between the distal portion andthe proximal portion, wherein the proximal portion comprises: a shaftcomprising a second outer diameter larger than the first outer diameter;and a proximal end comprising a proximally facing transition from thefirst diameter to the second diameter.
 2. The prosthesis deliverycatheter assembly of claim 1, wherein the proximally facing transitioncomprises a concave shaped surface.
 3. The prosthesis delivery catheterassembly of claim 1, wherein the proximally facing transition comprisesan inclined surface.
 4. The prosthesis delivery catheter assembly ofclaim 1, wherein the outer sheath comprises a lumen, and wherein theshaft is disposable within the lumen.
 5. The prosthesis deliverycatheter assembly of claim 1, wherein the inner sheath comprises alumen, and wherein the distal tip comprises a lumen in communicationwith the lumen of the inner sheath.
 6. The prosthesis delivery catheterassembly of claim 1, wherein the distal portion comprises a radiallyinward taper extending from the shoulder to a distal end of the distalportion.
 7. The prosthesis delivery catheter assembly of claim 1,wherein the distal tip comprises a nylon material.
 8. The prosthesisdelivery catheter assembly of claim 7, wherein the nylon material is apolyether block amide.
 9. The prosthesis delivery catheter assembly ofclaim 1, wherein the inner sheath and the distal tip comprise a unibodyconstruct.
 10. A prosthesis deployment device, comprising: a prosthesisdelivery catheter assembly comprising: an outer sheath; an inner sheathdisposed within the outer sheath, the inner sheath comprising a firstouter diameter; and a delivery tip disposed at a distal end of the innersheath, the delivery tip comprising: a distal portion; a proximalportion; and a shoulder disposed between the distal portion and theproximal portion, wherein the proximal portion comprises: a shaftcomprising a second outer diameter larger than the first outer diameter;and a proximal end comprising a proximally facing transition from thefirst diameter to the second diameter; a pliant member surrounding aportion of an exterior surface of the inner sheath, the pliant memberconfigured to engage a constrained prosthesis; and an actuator operablycoupled to the outer sheath and configured to proximally translate theouter sheath relative to the constrained prosthesis to deploy theconstrained prosthesis.
 11. The prosthesis delivery catheter assembly ofclaim 10, wherein the proximally facing transition comprises a convexshaped surface.
 12. The prosthesis delivery catheter assembly of claim10, wherein the proximally facing transition comprises an inclinedsurface.
 13. The prosthesis delivery catheter assembly of claim 10,wherein the outer sheath comprises a lumen, and wherein the shaft isdisposable within the lumen.
 14. The prosthesis delivery catheterassembly of claim 10, wherein the inner sheath comprises a lumen, andwherein the delivery tip comprises a lumen in communication with thelumen of the inner sheath.
 15. The prosthesis delivery catheter assemblyof claim 10, wherein the distal portion comprises a radially inwardtaper extending from the shoulder to a distal end of the distal portion.16. The prosthesis delivery catheter assembly of claim 10, wherein thedelivery tip comprises a nylon material.
 17. The prosthesis deliverycatheter assembly of claim 16, wherein the nylon material is a polyetherblock amide.
 18. A method of deploying a prosthesis, comprising:proximally translating an outer sheath of a prosthesis delivery catheterrelative to a prosthesis; deploying the prosthesis from an inner sheath;proximally displacing the inner sheath relative to the deployedprosthesis, wherein a proximally facing transition of a distal tipcoupled to the inner sheath is displaced through the deployed prothesiswithout catching on any portion of the prosthesis.
 19. The method ofclaim 18, wherein the proximally facing transition comprises a convexshaped surface.
 20. The method of claim 18, wherein the proximallyfacing transition comprises an inclined surface.